S52 OBDI chips - including large MAF + injector tunes

[matt]

Fuel trims are calculated at part throttle and applied globally.

The ECU can read and react to all of its sensors very quickly even at max engine speed. There is a really simple reason for this, not hard to deduce. It has to do with AFR targets part throttle vs full throttle and how an oxygen sensor works.

[BimmerToad]

Comparing chips is hard. If you just swap them on the dyno and see what happens, the results are nearly meaningless. You need to run the car for a relatively long time with each chip to let the ECU adapt and then dyno each chip. This gets expensive if you're trying to do it all on the dyno. If you do the pulls on different days, the different conditions can throw the power off also. It's sort of a catch 22.

From my understanding, aren't adaptive fuel trims only involved with partial throttle performance, for the Bosch OBD1 system? WOT doesn't learn because the rate of change in the engine parameters is much quicker than the system can react to. Correct me if I'm wrong.

Now, I understand that comparing one chip to another is meaningless if the engines and dynos are different ...

[matt]

Just saw that over at the other place...

http://forums.bimmerforums.com/forum/showpost.php?p=11200976&postcount=98

[SchnellerVert]

The guy from SC with the 525iT with the swapped S52 just commented on your chip, said he was very happy with it compared to the TMS/Jim C chip.

[matt]

What exactly needs to adapt in the ECU? Kudos on the S52 software, you'll be hearing from me soon :-)

The fuel trims are set on the engine we use to tune the chip. Your engine may not have exactly the same intake track or exactly the same amount of gunk built up on your MAF or any number of other things. Your oxygen sensor will read the actual air fuel ratio under certain conditions and calculate an adjustment to the fuel settings in the chip for your specific motor. This is why it's so important to use an oxygen sensor.

[etxxz]

i want ibdII software :(

[vr4boy]

i purchased one of Matt's chips and installed it in my 90 e30m3 w/an s52 obd1 conversion last weekend.
i am very pleased with the performance-the engine runs way better now w/ the new chip/software- it brought out the "beast" hiding in that s52-pretty much could feel the difference with the butt dyno test:-)
prior to installing the chip-i was running the motor temporarily w/ a 413 red labelled ecu off a 93 325is(stock tune for a 2.5 engine w/ green top injectors) i guess with the miss-matched software between the 413 and the s52-it robbed the motor of performance and made it run rough-i noticed it being on the rich side.
performance is way up now and the term scolded dog comes to mind....

economy wise it helped too, as i notice some good gas mileage- i'm not getting that "running rich" feeling anymore(unburnt gas smell at the exhaust).

The Racer's Market(TRM) has a good product here and i give them a two thumbs up! (good product and good price).

on a side note,Matt's right about the ecu needing to "learn or adapt" ...after swapping in the chip,i noticed a dramatic performance improvement after about 50 miles of the learning stage....

next years plan is to drop in supercharger:-)

[lateapex31]

What exactly needs to adapt in the ECU? Kudos on the S52 software, you'll be hearing from me soon :-)

[matt]

Comparing chips is hard. If you just swap them on the dyno and see what happens, the results are nearly meaningless. You need to run the car for a relatively long time with each chip to let the ECU adapt and then dyno each chip. This gets expensive if you're trying to do it all on the dyno. If you do the pulls on different days, the different conditions can throw the power off also. It's sort of a catch 22.

[static]

any dynos/comparos to similar offering from JimC? (Turner) that's what i have and i am lovin' it

[BimmerToad]

I'd like to hear any feed back on the NA S52 chip. My AA tuning is decent, at best :?

[matt]

I don't start too many threads to plug our products in here, but I have had a lot of PMs and posts about S52 software, so I wanted to let you guys know it's up on the site and ready to ship out. There are actually two guys on here running this software already... maybe they'll chime in and let us know how they like it? :mrgreen:

http://www.racersmarket.net/catalog/product_info.php?cPath=32&products_id=98

Turbo chips are on the site also:

http://www.racersmarket.net/catalog/product_info.php?products_id=130&osCsid=aac37be3116002edbf2c5264a5643e23

Thanks guys!

Almost forgot: The coupon code R3VSHIP is good for free USPS shipping on a chip (and almost anything you buy with it) in the lower 48 states.